Astronomers have launched an historic search for life elsewhere in the universe, scanning through 10 million star systems – and turning up nothing. The search, which the researchers claim was broader than any before, looked through a patch of the universe in the hope of finding radio emissions that could be coming from an intelligent source.
These “technosignatures” are made up of powerful blasts of radio frequencies similar to those that come from an FM radio, and so could indicate that they are coming from an intelligence civilisation. But the researchers heard nothing from that patch of sky, which was located around the constellation of Vela.
That was despite a scan that lasted 17 hours, which researchers said was 100 times more broad and deep than previous similar studies. It used the Murchison Widefield Array, or MWA, a large telescope located in the outback of Western Australia.But astronomers said that while there may be disappointment not to have heard from an alien civilisation, they were not surprised by the result.
The research still only examined a relatively tiny patch of the sky, and it is very possible that alien life would not give off those kinds of radio signals. “As Douglas Adams noted in The Hitchhikers Guide to the Galaxy, ‘space is big, really big’,” said Steven Tingay, one of the astronomers involved in the project, in a statement. “And even though this was a really big study, the amount of space we looked at was the equivalent of trying to find something in the Earth’s oceans but only searching a volume of water equivalent to a large backyard swimming pool.
“Since we can’t really assume how possible alien civilisations might utilise technology, we need to search in many different ways. Using radio telescopes, we can explore an eight-dimensional search space. “Although there is a long way to go in the search for extraterrestrial intelligence, telescopes such as the MWA will continue to push the limits – we have to keep looking.”
Researchers hope to conduct similar searches using the Square Kilometre Array, a similar but much larger piece of equipment that will allow them to detect radio signals from relatively nearby star systems and survey billions of possible candidates.